JP2000344396A - Image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image recorder positively writing without displacement of an image position of a paper sheet with respect to an image position of a document and accurately writing the image onto a writing position by maintaining without impairing a detection accuracy of a deviation detecting sensor. SOLUTION: In this image recorder equipped with a deviation detecting sensor 35 provided at a paper sheet conveyance part between a paper sheet feeding part and a transfer part and detecting a deviation of a paper sheet from the paper sheet feeding part, a reading reference position of an original preset in a main scanning direction from a far end part of a mount table for document reading and a deviation detecting reference position XO of a paper sheet 1 preset in the main scanning direction of the deviation detecting sensor 35 are determined in the same positional relationship.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus and, more particularly, to an image recording apparatus which writes an image on a sheet without deviating from the image position of a document, and maintains the image without deteriorating the detection accuracy of a shift detection sensor. The present invention relates to an image recording device for writing an image.

[0002]

2. Description of the Related Art Image recording apparatuses are used in various apparatuses such as copying machines and fax machines. FIG. 4 is a sectional view of a main part of an image recording apparatus that has been conventionally used.

When an image is copied by this image recording apparatus, a copy sheet 1 (for example, A4 size paper) fed from a paper feed unit (not shown, the same applies hereinafter) as shown by an arrow (a). ) Is transported through the paper transport unit 10 and is fed out to the transfer unit 20. After the image is transferred in the transfer unit 20 and further the fixing is performed, the sheet 1 is discharged to the outside.

[0006] The paper transport unit 10 includes a registration roller 12.
, A guide section 17 and a pre-transfer roller 11,
The paper 1 is conveyed by these and fed out to the transfer unit 20.

[0005] The guide portion 17 is provided with a shift detection sensor 15.
a, a mirror 15b, and a CCD 15c as a light receiving unit, and detects a deviation when the sheet 1 is conveyed.

FIG. 5 is a plan view of the paper transport section 10 shown in FIG. The sheet 1 is conveyed through the guide section 17 and the pre-transfer roller 11 after the inclination of the sheet 1 is adjusted by the registration roller 12, and the sheet 1 is conveyed from the sheet feeding section. (In the direction perpendicular to the arrow (a) in FIG. 2), the deviation may be ± ΔX from the deviation detection reference position X of the sheet 1. The offset detection sensor 15 detects this variation, and can correct the offset and write an image at a predetermined position even if the transport of the sheet 1 varies.

FIG. 6 is a plan view of a document table 3 for reading a document 2 (for example, A4 size). The document table 3 includes a display unit 4, an operation unit 5, and document abutting units 6a and 6
The document 2 is abutted against the document abutting portions 6a and 6b, and the document 2 is read based on the reading reference position 7 of the document 2 in the main scanning direction. The document reading section 8 reads a document fed by an automatic document feeder (not shown), and performs reading based on a reading reference position for the document reading section 8 which is also provided separately.

[0008]

However, the conventional image recording apparatus has the following problems.

As described above, the original 2 is placed in the original abutment section 6.
The paper 1 is transported by the paper transport unit 10 from the paper feed unit, and is transferred to the upper surface of the paper 1 by the transfer unit 20. Is transferred and copied, the position 7a (see FIG. 4) on the back side of the top of the sheet 1 corresponds to the reading reference position 7 when the original 2 is set.

However, the shift detection sensor 15 is disposed on the near side as shown in FIG.
Is transferred to the paper 1 on the basis of, if the size of the paper 1 varies in the direction perpendicular to the transport direction (the main scanning direction), the image of the paper 1 by the size variation of the paper 1 The position is shifted from the image position of the document 2. In particular, when performing double-sided copying, the quality is not preferable. When the reference positions of the paper 1 and the document 2 are different as described above, the rotation unevenness of the polygon motor appears as a magnification error in the main scanning direction. It will be shifted from the image position.

Further, the scaling ratio of the paper 1 from the standard to the standard is usually rounded to 1/100 unit.
3 to A4 and B4 to B5 are 0.7 (70%) or 0.7 (71%). The image position of the sheet 1 is shifted from the image position of the document 2 by the difference between the two (0.007 or 0.003).

As described above, if the positional relationship between the offset detection reference position X of the sheet 1 and the reading reference position 7 when the document 2 is set is different, the image position of the sheet 1 may be shifted from the image position of the document 2. There is a problem that there is. Further, the same problem occurs when a document fed by the automatic document feeder (not shown) is read by the document reading unit 8.

Further, there is the following problem.

The paper passing interval L (see FIG. 4) for guiding the paper 1 provided in the paper transport unit 10 is usually 2 mm in order to transport the paper 1 smoothly. The shift detection sensor 15 includes an LED 15a of a light emitting unit, a mirror 15b, and a CC of a light receiving unit.
D15c is used to detect the deviation of the paper 1 during conveyance, but the paper passing distance L0 between the paper guide plate 18 and the guide plate is also set to 2 mm at the detection position of the paper 1 by the deviation detection sensor 15. For this reason, it is assumed that the sheet 1 passes through the center of the half of 2 mm, that is, 1 mm, that is, the center of the sheet passing interval L0 (see FIG. 4). However, the sheet 1 may vary without passing through the center.

Accordingly, since the position of the sheet 1 passing below the deviation detecting sensor 15 varies, the detection accuracy of the deviation detecting sensor 15 is reduced, and the deviation of the sheet 1 is corrected and the image is shifted to a predetermined position. There is also a problem that writing may not be performed accurately.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and reliably writes an image position of a sheet with respect to an image position of an original without deteriorating the detection accuracy of a shift detection sensor. It is another object of the present invention to provide an image recording apparatus for accurately writing an image at a writing position.

[0017]

Therefore, the image recording apparatus of the present invention includes a shift detecting sensor provided in a sheet conveying section between a sheet feeding section and a transfer section to detect a shift of a sheet from the sheet feeding section. In the image recording apparatus, a reading reference position of the document set in advance in the main scanning direction from the abutment portion of the mounting table for reading the document, and a deviation detection reference position of the sheet preset in the main scanning direction of the deviation detection sensor. It is characterized by the same positional relationship.

Also, in an image recording apparatus provided with a shift detecting sensor provided in a sheet conveying section between a sheet feeding section and a transfer section to detect a shift of a sheet from the sheet feeding section, a document reading of the automatic document conveying apparatus is performed. The document reading reference position preset in the main scanning direction of the set and the deviation detection reference position of the paper preset in the main scanning direction of the deviation detection sensor have the same positional relationship.

Also, in an image recording apparatus provided with a shift detecting sensor provided in a sheet conveying section between a sheet feeding section and a transfer section to detect a shift of a sheet from the sheet feeding section, the image recording apparatus is provided near the shift detecting sensor. The paper passage interval of the paper guide section is narrower than the paper passage interval of another paper guide section provided between the paper supply section and the transfer section.

The paper guide portion adjacent to the deviation detection sensor has a paper passage interval of ３ to の of the paper passage interval of another paper guide portion provided between the paper supply portion and the transfer portion. It is characterized by the following.

Further, the paper guide portion adjacent to the shift detection sensor has a part of a guide plate facing the shift detection sensor formed in a convex shape, and is formed by a sheet guide portion provided between the sheet feeding portion and the transfer portion. It is characterized in that the paper passing interval is narrowed.

Further, the sheet guide portion adjacent to the shift detection sensor has a flexible member having a convex shape on a guide plate facing the shift detection sensor, and another sheet provided between the sheet feeding portion and the transfer portion. The paper passage interval is narrower than the guide portion.

[0023]

Embodiments of the present invention will be described below.

FIG. 1 is a plan view of a sheet transport section 30 of the image recording apparatus according to the present invention.

Hereinafter, FIGS. 1 to 3 relating to the present invention will be described.
Here, the same reference numerals as those shown in FIGS. 4 to 6 of the conventional example are denoted by the same reference numerals.

The paper transport section 30 is provided between a paper feed section (not shown, the same applies hereinafter) and a transfer section (not shown, the same applies hereinafter). The sheet 1 is conveyed through the registration roller 12, the guide portion 37, and the pre-transfer roller 11 in the conveyance direction (A) indicated by the arrow.

The shift detection sensor 35 is disposed on the back side of the sheet conveying section 30 and performs main scanning in a direction perpendicular to the conveying direction (a) of the sheet 1 and detects a deviation detection reference position X0 in the main scanning direction of the sheet 1.
The deviation of the sheet 1 is detected based on.

Therefore, the reading reference position 7 in the main scanning direction of the original 2 (see FIG. 6) and the offset detection reference position X0 of the paper 1 in the main scanning direction should be in the same positional relationship with respect to the image of the original 2. The image can be written on the sheet 1 without shifting from the image position of the document 2. Similarly, when a document fed by an automatic document feeder (not shown) is read by the document reading unit 8 (see FIG. 6), the sheet 1 is similarly positioned with respect to the image position of the document of the automatic document feeder. Images can be written without shifting.

The reading reference position 7 of the original 2 is the position of the abutment 6a of the mounting table 3 for reading the original.
a, a shift detection reference position X0 of the sheet 1 is set at an end of the sheet 1 where the transport position is set in advance, and a shift detection sensor is set from the end. The position may be set in advance in the 35 main scanning directions.

FIG. 2 is a cross-sectional view of a sheet transport section 30 of an image recording apparatus according to another embodiment of the present invention. The paper transport unit 30 is provided between the paper feed unit and the transfer unit, as in FIG.

The sheet transport section 30 includes a registration roller 12 having two rollers 12a and 12b for adjusting the inclination of the sheet 1 fed from the sheet feeding section, a guide section 37, and two rollers 11a and 11b. And a pre-transfer roller 11 having the following.
Transported to The guide portion 37 is composed of a paper guide plate 31 and a paper guide plate 32, and the paper 1 is transported between the paper guide gaps L between the paper guide plate 31 and the paper guide plate 32. The paper guide plate 32 is provided with a shift detection sensor 35 for detecting the shift of the sheet 1 from the sheet feeding unit, and the writing position control that corrects the shift of the sheet 1 based on the detection result of the shift detection sensor 35 is performed. Done.

The paper guide plate 31 has a trapezoidal convex portion 50, and the paper passage gap L0 below the deviation detection sensor 35 is set smaller than the paper passage gap L. Therefore, the sheet 1 can pass through the lower portion of the shift detection sensor 35 without variation, and the image can be accurately written at the writing position while maintaining the detection accuracy of the shift detection sensor 35 without deteriorating.

The trapezoidal projection 50 provided on the paper guide plate 31 has a short length in the transport direction (a).
Is provided in the vicinity of the registration roller 12 from which the sheet 1 is sent out, so that the conveyance of the sheet 1 is performed smoothly.

FIG. 3 is a cross-sectional view of a sheet transport section 40 of an image recording apparatus according to still another embodiment of the present invention.
The paper transport section 40 is provided between the paper feed section and the transfer section, as in FIG.

The paper transport unit 40 includes a registration roller 12 having two rollers 12a and 12b for adjusting the inclination of the paper 1 fed from the paper supply unit, a guide unit 47, and two rollers 11a and 11b. And a pre-transfer roller 11 having the following.
Transported to The guide section 47 is composed of a paper guide plate 41 and a paper guide plate 42, and the paper 1 is transported between the paper passing gaps L between the paper guide plate 41 and the paper guide plate 42. The paper guide plate 42 is provided with a deviation detection sensor 45 for detecting deviation of the sheet 1 from the paper feeding unit, and performs writing position control in which the deviation of the sheet 1 is corrected based on the detection result of the deviation detection sensor 45. Will be

The paper guide plate 41 has a trapezoidal shape such as P
It has a flexible member 60 formed of a P material, and the paper passage gap L0 below the shift detection sensor 45 is set smaller than the paper passage gap L. The flexible member 60 passes through the opening 48a and is attached to the paper guide plate 41 at the stop 61.

Accordingly, the paper 1 can pass through the lower portion of the shift detection sensor 45 without variation by the flexible member 60, and maintain the detection accuracy of the shift detection sensor 45 without deteriorating the image writing position. Can be written accurately.

The flexible member 60 has a trapezoidal shape. However, the present invention is not limited to this. For example, a flat plate-shaped member may be used with an inclination, or a bent portion may be used. It is also possible to narrow the paper passing gap L by using a material.

Further, the flexible member 60 provided on the paper guide plate 41 has a short length in the transport direction (a) and is provided near the registration roller 12 from which the paper 1 is fed. Is carried out smoothly.

In the above-described embodiment, a copying machine as an image recording apparatus has been described as an example. However, the present invention is not limited to this, and can be widely used for faxes and the like.

[0041]

According to the present invention, there is provided an image recording apparatus provided with a shift detecting sensor provided in a sheet conveying section between a sheet feeding section and a transfer section for detecting a shift of a sheet from the sheet feeding section. Since the original reading reference position preset in the main scanning direction from the abutment portion of the document reading mounting table and the deviation detection reference position preset in the main scanning direction of the deviation detection sensor have the same positional relationship. In this case, the image can be reliably written on the sheet without shifting from the image position of the document.

Also, in an image recording apparatus provided with a shift detecting sensor provided in a sheet conveying section between the sheet feeding section and the transfer section to detect a shift of the sheet from the sheet feeding section, a document reading section of the automatic document conveying apparatus is provided. The original document reading reference position preset in the main scanning direction and the deviation detection sensor preset deviation detection reference position in the main scanning direction have the same positional relationship. The image can be reliably written without any deviation from the image position.

Also, in an image recording apparatus provided with a shift detecting sensor provided in a sheet transporting section between a sheet feeding section and a transfer section to detect a shift of the sheet from the sheet feeding section, a sheet close to the shift detecting sensor is provided. Since the paper passage interval of the guide portion is narrower than the paper passage interval of another paper guide portion provided between the paper supply portion and the transfer portion, the paper can pass through the lower portion of the deviation detection sensor without variation, and the deviation can be reduced. An image can be accurately written at the writing position while maintaining the detection accuracy of the detection sensor without loss.

The paper guide portion adjacent to the deviation detection sensor has a paper passage interval of ３ to の of the paper passage interval of another paper guide portion provided between the paper supply portion and the transfer portion. Therefore, the sheet can surely pass through the lower portion of the shift detection sensor while preventing the variation, and the image can be accurately written at the writing position while maintaining the detection accuracy of the shift detection sensor. .

Further, the paper guide portion adjacent to the deviation detection sensor has a part of the guide plate facing the deviation detection sensor formed in a convex shape, and is formed by a paper guide portion provided between the paper supply portion and the transfer portion. Since the paper passing interval is narrowed, the paper can pass through the lower portion of the shift detection sensor without variation with a simple structure, and the image can be accurately written at the writing position while maintaining the detection accuracy of the shift detection sensor. Can be written to.

Further, the paper guide portion adjacent to the shift detection sensor includes a flexible member having a convex shape on a guide plate facing the shift detection sensor, and another sheet provided between the sheet feeding portion and the transfer portion. Since the paper passing interval is narrower than the guide portion, the paper can pass through the lower portion of the deviation detection sensor without variation with a simple and inexpensive structure, and the image is written without deteriorating the detection accuracy of the deviation detection sensor. It is possible to write accurately at the insertion position.

[Brief description of the drawings]

FIG. 1 is a plan view of a sheet transport unit of an image recording apparatus according to the present invention.

FIG. 2 is a cross-sectional view of a sheet transport unit of an image recording apparatus according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view of a sheet transport unit of an image recording apparatus according to still another embodiment of the present invention.

FIG. 4 is a sectional view of a main part of an image recording apparatus that has been conventionally used.

FIG. 5 is a plan view of the paper transport unit shown in FIG.

FIG. 6 is a plan view of a document table for reading a document.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 paper 2 original 3 original mounting table 6a, 6b original abutment section 7 reading reference position 8 original reading section 10 paper transport section 11 pre-transfer roller 12 registration roller 15, 35, 45 offset detection sensor 16 contact glass 17 guide section 20 transfer Units 30, 40 Paper transport unit 31, 32 Paper guide plate 18, 31, 32, 41, 42 Paper guide plate 37, 47 Guide unit 48a Opening 50 Trapezoidal protrusion 60 Flexible member 61 Stop X, X0 Deviation detection reference position L, L0 Paper clearance

Continued on front page (72) Inventor Jun Yokobori 2970, Ishikawacho, Hachioji-shi, Tokyo Inside Konica Corporation (72) Inventor Tetsuya Niizuma 2970, Ishikawacho, Hachioji-shi, Tokyo Inside Konica Corporation (72) Inventor Shiroichi Tokuo 2970 Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Tadayoshi Ikeda 2970 Ishikawa-cho, Hachioji-shi, Tokyo Inside Konica Corporation F-term (reference) 2H027 DC00 DE02 ED04 FA22 2H071 DA01 DA22 DA32 EA06 2H072 AA03 AA09 AA16 AA22 AB07 CA01 CB07 3F048 AA02 AA04 AB01 BA22 CC05 DA06 DA07 DB06 DC14 3F101 FA05 FA06 FB01 FB04 FC11 FC18 FE17 LA02 LA05 LB03

Claims (6)

[Claims] An image recording apparatus provided in a sheet transport section between a sheet feeding section and a transfer section and provided with a shift detecting sensor for detecting a shift of a sheet from the sheet feeding section. An image recording apparatus, wherein a reference position for reading a document preset in the main scanning direction from the abutting portion and a reference position for deviation detection of a sheet preset in the main scanning direction of the deviation detection sensor have the same positional relationship. . 2. An image recording apparatus, comprising: a sheet detecting section provided in a sheet conveying section between a sheet feeding section and a transfer section to detect a shift of a sheet from the sheet feeding section. An image recording apparatus, wherein a reference position of a document set in advance in a main scanning direction of a document and a reference position of deviation detection of a sheet preset in a main scanning direction of a deviation detection sensor have the same positional relationship. 3. An image recording apparatus provided with a shift detecting sensor provided in a sheet conveying section between a sheet feeding section and a transfer section for detecting a shift of a sheet from the sheet feeding section, wherein the image recording apparatus is located close to the shift detecting sensor. An image recording apparatus, wherein a paper passage interval of a paper guide unit is narrower than a paper passage interval of another paper guide unit provided between the paper supply unit and the transfer unit. 4. A sheet guide portion adjacent to the shift detection sensor has a sheet passing interval of ／ to の of a sheet passing interval of another sheet guide portion provided between the sheet feeding portion and the transfer portion. The image recording apparatus according to claim 3, wherein 5. A paper guide provided in the vicinity of the deviation detection sensor, wherein a part of a guide plate facing the deviation detection sensor has a convex shape, and another paper guide provided between the paper supply unit and the transfer unit. The image recording apparatus according to any one of claims 3 to 4, wherein a sheet passing interval is narrower than a set. 6. A paper guide unit proximate to the shift detection sensor includes a flexible member having a convex shape on a guide plate facing the shift detection sensor, and is provided between the sheet feeding unit and the transfer unit. The image recording apparatus according to any one of claims 3 to 4, wherein a sheet passing interval is narrower than the sheet guide portion of (1).